Azo dyestuffs



. tive containing at least Patented Dec. 27, 1932 UNITED STATES KARLHOLZACH, OF LUDWIGSHAFEN-ON- PATENT o icE HEIM, AND WERNER MUELLER, OFLUDWIGSHAFEN1ONEHE-5RHINE,.GERMAJSIX; s

or DELA AR No Drawing. Application filed March 8,

The present invention relates to new droxy azo dyestuffs.

NVe have found that valuable o-hydroxy azo dyestuffs can be obtained by.diazotizing a sulfonated aromatic o-hydroxy amino compound, which termis meant to comprise o-amino phenols, o-aminonaphthols, and theirderivatives, and combining them with an unsulfonated monohydric phenolderivatwo further substituents one of which is in the para-position tothe hydroxyl group. Phenol derivatives according to thepresent'in-vention comprise for example, p-chlor-m-cresol (CH OH: Cl= l3: 6), 2.4-dimethyl-phenol m-Xylenol), 2.4.5-trimethyl phenol-(pseudocumenol), also 3-amino-4 methylpheno1, and others. I

The dyestuffs obtainable according to this invention are distinguishedbv a great coloring power and good equalizing properties in dyeing. Thedyeings on wool are extremely fast after an after-treatment withmetallic salts, such as salts of chromium or copper. Depending on theo-hydroxydiazo compound and phenol derivative employed, red, violet,brown, olive green or black shades are obtained.

The following examples will further illustrate the nature of thisinvention but the invention is not restricted to these examples. Theparts are by weight.

Example 1 7 0.2 parts of 4-nitro-2saminophenol-G-sulfonic acid arediazotized with 40 parts of 19 Baum hydrochloric acid and 20.7 parts ofsodium nitrite, in the usual way. The diazo solution is allowed to runslowly into an ice-cold solution of ll parts of asymmetric m-Xylenol(QA-dimethyl phenol), 35 parts of 40 Baum caustic soda solution, about600 parts of water, and 150 parts of sodium carbonate. The mixture isstirred at about 5 to 10 centigrade until the formation of the dyestufi'is complete, whereupon sufficient common salt is added to efiect thecomplete deposition of the dyestuff. WVhen filtered and dried, the newdyestuif is in the form of a black-brown powder, which readily dissolvesto a yellow brown solution in water,

(asymmetric srenons 1:0 GENERAL ANILINE wonxs; me, on NEW rzonx, N. Y.,A .oonronn'rron z o DYESTUFFS 7 1925 Serial N0. 345,590, and in GermanyMarch 10, 1928.

the color changing to cherry red on the ad dition of caustic soda, or toreddish yellow with acetic acid. The dyestuff gives pale yellow-browndyeings on wool, turning'to a deeper brown shade with yellowishsheen onchroming' l Y If the 4-nitro-2 aminophenol-6-sulfonic acid in the aboveexample is replaced by ,a corresponding amount of 6-nit ro-2-amiriophenol-4-sulfonic acid, a similar ,dy'es tiilfis obtained, which givesredbrown dyeings on wool, changing to blaclebrown on treatment withbichromate.

Ewample 2 44.7parts of .4-chloro-2-amino phenol-,G- I

sulfonic acid are diazotized with 30 arts of 19 :Beaum hydrochloriciacidand v13.8 par-ts of sodium nitrite in the ,usual way. A .solution :isprepared by warming '30 pants gQf pseudocumenol 2.4:.5-trimethylphenol)with 25 parts of 40 Beaumcausticsoda solution in'about 400 parts ofwater,-;100 parts of sodium carbonate being added, and the Whole iscooled .with ice .to 7 to 85 centigrade; The above diazo solution isallowed to run moderately into the solution of the ,couplin component.The formation vo-f the dyestu proceeds gradually, the mixture isstirredat a low temperature until the formationof-the dyestufl' is finished;thedyestuff issalted out, filtered an ri The new 'dyestu-fi' a red-brownpowder which is very readily soluble, toa dark brown solution, in water.It gives from an acid loathbrown-reddyeings on .wool thecolor {be- .ingchanged ,to dark brown ;by chroming, which latter improves the fastnessproperties very considerably. i

IfpseudocumellOl is combined with diazotized et-nitro-Q-aminophenol-fi-sulfonic acid ina similar manner, a new dyestufi' is obtainedwhich gives red-brown dyeingson woolfr om an acid bath, extremely evenolive-brown shades being produced by chroming.

Example 3 .parts of 4-,chlor-2-amino lphenol-fi-lsul;-

.fonicacid, .inaqueous olution, are diazotizled in the presence of aboutBeaumhydrochloric acid and'ace, w th :the

necessary amount of sodium nitrite, at about O5 centrigrade in the usualway. The diazo solutionis stirred into a solution containing 39 parts ofo-amino-p-cresol, and the equiva-V lent quantity of'clausticsodasolution, together with a suiiicient amount of sodium carbonate to keepthe reaction alkaline throughout the coupling process, which is-fairlyrapidr Aft-' the mixture is warmed-and the dyestuil is 'salted out witherstirring forsevera'l hours,

common salt. It is distinguished by a great tlnctorlal power, and lugsone wool, turning black on chronnng."

' v The dyestuli obtainable from the nitrated.

compound of 1 amino 2 naphthol t sulton c acid and o-ammo-p-cresol in asimilar manner ields a handsome, strong, iast bl'ack' shadewhen chromed,r 1 v y g The o-amino-p-cresol used as coupling component may bereplaced by a derivative thereof substitutedin the amino group, forexample, the, monoor. 'diallqyl derivatives, by

means of which variations in the depth of tint can beobtained.

Example 1 70.2 parts of l-nitro-Q-aminophenol-fi suL fonic acid arediazotized as described in EX- ample -1, the solution is then allowed to"run into a solution of 47 parts of l-chlor-iS-methylphenol and theequivalent amount of caustic soda and about parts of sodium carbonate.When the coupling is completed, the mixture is warmed,- and'the dyestufii's salted out in the usual' manner. The dyestuflVdissolves in water togive a brown'solution and dyes wool from an acid bath brownish yellowshades,

- 1 The dyeings on wool give fast-yellow-brown L component.

shades on 'ch'roming; In this case also, the tone,'equa'lizingproperties and the like, can be modified by varying the substituents,both in the diazo compound and in the coupling Whatwe' claim iszw 1. Asnew articles of manufacture the o liy'c'lroxyazo "dyestufi's obtainableby coupling a diazotized 'sulfona'ted' o-hydroxyamino comp'oiund of thebenzene or naph: thalene series 'Withan unsulfonated mono liydric'phenol containing only substituents I "3: As a" new articleof'manufactu'rg-the gives bright brown 'dy'e-- to a fast, deepVlOlQilo-hydroxyazo dyestuil corresponding to the formula:

forming a'black-brown powder, dissolving to a yellow brown solution inwater, the color of which changes to cherry red on the addition ofcaustic soda and to. reddish yellow on the addition o fa'ceticacid, andgiving yellow brown'dyeings on wool turningto a deeper brown withyellowish sheentonchrom ng.

L- The o-hydroxyazo dyestu-fi' correspondingtothehformula: i y i: v.

dyeing wool brown-red shades from anacid bath, the color beingchanged'to dark brown by; chroming. I a i 5; The o-hydroxyaz 'o dyestuficorrespond ing to the formula: q

the 4-chlor-3-methylphenol radical I is attached probably in its6-positi0n to the azo bridge, which dyestufi dissolves in water to givea brown solution and dyes woolfrom an acid bath brownish yellow shadeswhich become yellowish brown on chroming. g

In testimony whereof we have hereunto set our hands.

KARL HOLZACH. HANS'KRZIKALLA.

least twoofwhich must diazoti'zed 4-nitro-2-aminophenol-6- v MUELLER--r.

. i y 9Q forming afred-brown powder readily soluble, in water to give adark brown solution and.

